Flow device



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Filed Feb. 4, 1939 Patented Dec. 30, 1941 UNITED STATES,, PATENT OFFICE FLOW DEv-IoE Roy A. Lamb and William, H. Waring, Dallas,

Texl, assignors to Merla Tool Corporation, Dallas, Tex., a corporation of Texas Application February 4', 1-959, Serial :NOuZl545558 15 Claims. Cl. .1'03-I232) This invention relates to new and useful improvements in flow devices.

One object of the invention is to provide an improved device for controlling the admission of a lifting fluid, such as gas or air, into a liquid L" column whereby said column is lifted or raised'by said fluid, the device being particularly adapted for use inoil wells to lift the well liquids to the surface.

An important object of the invention is to i provide an improved flow device which is arranged to be run into and removed from the well bore by means of a flexible element, such as a wire line or cable, whereby insertion and removal thereof is possiblewithout pulling the tubing, -as is the usual practice.

Another object of the invention is to provide Fan improved well flow apparatu which includes a seating member connected in the tubing string at a desired elevation therein, together with a valve assembly arranged to be run into and removed from the tubing on a wire line and adapted to be removably supported in the seating member; the valve assembly being constructed so as to control the flow of a pressure lifting fluid 17" into the well liquid column standing in the Well casing, whereby said column is'lifted to the surface by said pressure fluid.

A particular object of the invention is to provide an improved flow device which isarranged to be removably seated in the well tubing and whichcontrols theflow of a lifting gas'from said tubing into'the well liquid in the well casingsaid device being actuated by a predetermined pressure differential between the liquid in the casing 1 Still another object of the invention is to provide an improved flow device, of the character described, wherein the valve element is provided with longitudinal flutes or grooves which conduct the lifting gas .past the element to the gas inlet opening, said flutesibeing associated -with'the cylinders in which the element is movable and being tapered or gradually reducedso that as the element moves toward .itsc'losed position, the reduced :ends .of the flutes approach the cylinder wall to cause the element to act with a piston effect since the cross-sectional area of the element is, in .efiect, exposed to the pressure moving the element to a closed position; such piston effect assuring the positive shutting or closing of thegasinlet aftereach charge of gas is admitted.

A construction designed to carry out the invention will .be hereinafter described, together with 7 other features of. the invention.

The invention will bexmore readily understood from a reading of the following specification and by reference to the accompanying drawings, in whichlan example of the invention is shown, and

wherein:

in positionprior to movement,

Figure iBisa view, vsimilarto Figure2, withthe valve element in intermediate position,

Figurei is a .viewsimilarto Figure 3, with the valve in shut-oil position,

Figure .5 is a horizontal, cross-sectionalview, taken ontheline 5--5.ofFigure 2,

Figure 6 is a horizontal, cross-sectional view, taken on the lineB-LG of Figure 2, and

Figure 57 is an enlarged detail, illustrating the .engagemento'f the valve with the seat.

In the drawings, the numeral .10 designates a Well casing which extends throughout the length of the well bore in the'usual manner. The lower end of the casing is open and the well liquid from the producing areaenters said casing and rises to-a level therein, which level varies with the particularconditions of thewell. The well tubing 'l'l extends .axially through the well casing and has its lower end open whereby communication between the interior or bore of said tubing and the bore of the casing is established. A flow device A is arranged to be mounted Within the well tubing and is preferably located below the normal standing liquid level th reof. As will be explained, the device is removably supported in the tubing and controls the admittance of a lifting medium, such as gasor air, from the tubing into the liquid column inthe casing. The lifting medium' is introduced into the upper end of the tubing -andmust flow downwardly through the device A in order to escape from the lower end of the tubing into the well casing l0.

The flow device A is particularly adapted to intermittently admit gas, as needed, to the liquid column to raise the same to the surface and may be termed an intermitter. The conditions of the well may be such that a period of time is required for the well liquid to bulid up to a normal standing level in the'casing and the device A is arranged to be actuated by the differential. in pressures between the gas in the tubing II and the liquid in the casing, as will be hereinafter explained, whereby a predetermined liquid level is necessary before gas is admitted to the liquid column to raise the same; After the liquid column is raised, the device A automatically shuts off the gas flowing into the casing through said device and the liquid level must again build up in said casing before gas is admitted thereto. Since the device A may be supported within the tubing at any desired elevation, it will be obvious that it may be readily employed in wells having a relatively low standing liquid level.

As has been stated, the flow device A is arranged tovbe removably'supported in the well tubing H and in carryingout the invention, an elongate supporting sleeve or nipple I2 is connected in the tubing. The sleeve has its ends externally screw-threaded to facilitate its connection in the tubing and said sleeve is located at any desiredelevation, being preferably below the normal standing liquid level, indicated at L in Figure 1. An internal, annular shoulder I3 is formed within the bore of the sleeve near its lower end and the'wall of the bore is bevelled immediately above said shoulder, as shown at l3. The annular bevel l3" and shoulder I3 form a seating surface for supporting the flow device A within the bore of the tubing.

The flow device A includes an elongate cylinder I5 which is constructed of anupper section I5a and a lower section I51),v which sections have screw-threaded connection. The lower section I5?) is formed with a reduced, externally screwthreaded collar l6 which receives the upper end of a tubular mandrel IT. The external diameter of the upper portion of themandrel is substantially equal to, or slightly less than,'the diameter of the bore I 4 of the supporting sleeve l2 so as to have a sliding fit therein (Figure 2), while the lower portion of the mandrel is reduced to provide a tubular shank IT, on which a plurality of inverted packing cups are mounted. The cups are constructed of an elastic packing material, and are spaced from each other by a spacer ring 19, the ring and cups being retained on the shank by an annular retaining collar 20 which is screwthreadedonto the lower end of the shank.

The collar 20 has a sliding fit within the bore 14 of the supporting sleeve l2 and the lower end of said collar is bevelled complementary to the bevel l3 above the shoulder l3. The lower edge of the collar is adapted to rest on the shoulder l3 with its bevelledportion engaging the bevel l3 within the bore l4 and in this manner, the mandrel I! and cylinder [5 are supported in the well tubing. When so supported, theouter surfaces of the inverted packing cups 3 engage the wall of the bore IA of the supporting sleeve and, manifestly, any, pressure in thebore of the tubing above said cups acts on said cups to distort the same radially outwardly. whereby sealing ofi between the mandrel I! and the sleeve [2 is assured. Therefore, when the collar 20 is seated and the cylinder -l5 and mandrel I! are supported acetic ii within the tubing, the well liquid in the tubing below the mandrel cannot flow upwardly between the mandrel and supporting sleeve; also, the lifting medium in the tubing above the mandrel can- I not by-pass said mandrel and, therefore, the only communication between the bore of the tubing above the device A and the bore of the tubing below said device must be through the bore of the cylinder [5 and through the tubular mandrel. It is pointed out that the pressure above the cups not only distorts the same into sealing position,

but also holds the assembly downwardly on the seat I3 to prevent upward displacement thereof by pressure from below.

The upper section l5a of the cylinder [5 is formed with an axial bore 2i which has its lower portion reduced at Zla to form an internal, annular shoulder 22. The upper end of the bore is provided with internal screw threads which are arranged to receive the lower portion of a tubular fishing neck 23. The upper end of theefishing neck is formed with the usual undercut shoulder 24, whereby a. suitable tool (not shown) may be engaged therewith tov permit lowering and raising of the device A on a Wire line or cable. Manifestly, when a, flexible element is employed to raise and lower the device A, the same may be quickly inserted or removed from the tubing without disturbing said tubing, whereby the labor and time required for inserting and removing the device is minimized. The lower portion of the fishing neck 23 extends into the bore 2| of the cylinder and the lower edge of said neck is bevelled to provide an annular seat 25.

The lower end of the upper section [5a of the cylinder engages within the bore 26 of the lower section l5b. The lower portion of the bore is reduced to provide an internal, annular shoulder 21 and the inner peripheral portion of this shoulder is bevelled to provide a valve seat 28. Below the valve seat the bore 26 is slightly enlarged so as to have a diameter substantially equal to the diameter of the bore of the mandrel l1 which is connected to the lower end of the cylinder l5. From the foregoing, it will be obvious that a lifting gas introduced into the upper end of the tubing I I may flow downwardly through said tubing and then through the tubular fishing neck, through the cylinder and finally through the tubular mandrel ll. This gas may then pass downwardly through the remainder of the tubing below the device A and from the lower end thereof into the well casing [0 to lift the well liquid upwardly through the well casing to the surface.

For controlling the flow of the lifting gas through the bore of the'cylinder 2i and thereby controlling the admittance ofthe lifting gas to the liquid column, an elongate plunger or piston 30 is slidably mounted within the cylinder 2|. The plunger has a sliding fit within the reduced portion 2la of the cylinder bore and its upper end projects into the upper portion of said bore. The extreme upper end of the plunger has an enlarged, conical head 3! preferably integral therewith and the head is adapted to engage the annular seat 25 formed at the lower edge of the fishing neck 23. When seated, the head closes the bore of the cylinder to prevent flowtherethrough. A coiled spring 32 surrounds the upper portion of the plunger, being confined between the head and the internal shoulder 22 within the bore, and said spring exerts its pressure to constantly urge the plunger upwardly so as to urge the head 3| toward its seat 25.

The lower end of the plunger is provided with a depending metering element or pin 33 which is, preferably integral therewith and projects axially therefrom. The outer surface or contour of the pin is subject to variationbut it has'been found preferable tomake the same along the lines of a logarithmic curve, whereby the pin is curved or tapered inwardly, the diameter thereof gradually reducing to an axial point or extremity. An external, annular shoulder 34- is formed immediately above the pin 33- at the lower end of the plunger or piston30 and when the plunger moves downwardly in thecylinder l (Figure 4), this shoulder is arranged to engage thebevelled seat 28 which is located within the lower section l5bof the cylinder; Manifestly, when the shoulder 34 engages the seat: 28, further downward movement of the plunger is arrested andflow pastthe seat is completelyshut off. It is'noted that the bevel or incline of the seat 28 is different from and is not complementary to the bevel or incline of 'the shoulder 34, whereby the shoulder engages the seat at one point only. This point contact reduces the possibility of foreign matter which might accumulate On the seat interfering with the positive seating of theshoulder, and

also causes the entire cross-sectional area of the plunger to be exposed to the pressures acting thereon (Figures 4 and '1).

Above the external shoulder 34at the lower end of the plunger, the outer surface of said plunger is formed with a plurality of vertically extending flutes or channels 35 whichare spaced around the lower portionof the plunger. The lower ends of the flutes terminate short of the shoulder 34, whereby a portion 34a of the outer surface of the plunger isdisposed between the ends of the flutes and said shoulder. When the plunger is .in its uppermost position (Figures 1 and 2) with the conical head 3| in a seated position, the lower ends of the flutes or channels are within the reduced portion 2la of, the .bore of the cylinder, while the upper ends of the flutes are above the internal shoulder 22, being exposed to the interior; of the enlarged upper por tion of the cylinder bore 21-. Manifestly, at this time, the lifting gas above the plunger cannot enter the boreof the cylinder since the head 3| is seated.

l The upper end of each flute or groove is gradually reduced as shown at 35' andthe length of the flutes is suchthat when the plunger moves to its lowermost position (Figure 4) with the shoulder 34 engaging the seat 28, theupper ends of said flutes are within the reduced portion 2la of the cylinder bore. Therefore, when the plunger is in a lowermost position, the lifting gas cannot flow past the plunger. It is pointed out that the flutes or grooves 35 provide by-pass channels to allow the lifting gas to flow downwardly past the plunger 30. When the plunger :is first moved downwardly to unseat the head 3 I,

the gas enters the bore 2| of the cylinder and :fl'ows downwardly through the flutes and then through the bore 26 of the lower cylinder section l5b to the tubing therebelow. The head 3i is tformed with vertical grooves or passages am.

As the plunger continues'its downward move- .ment, the metering pin 33 enters the reduced portion of the bore 26 below the seat 28 and .metering of the flow past the seat begins. At

the same time, the reduced upper portions 35 of the flutes 35 move toward the shoulder 22 to gradually reduce the by-pass opening for the gas flowing past; the plunger and, therefore, a doublemetering action is obtained. The reduc tion of the upper' end of the flutesmay be, comparable to the gradual reduction of" the surface of themetering pin, that is along the linesof a. logarithmic curve, so that the metering action of both these elements will be the same. However, the invention is not to. be limited to the flutes and pin producing exactly the same metering action as good results may be obtained without such relation between these parts. plained,-the upper ends of the flutes 35 enter thereduced portion2la of the cylinder bore 2| when the shoulder 34 engages the seat 28, whereby a double shut-off is provided. Of course, it would be possible to make the flutes slightly longer, in which event, the gas could continue to by-pass the plunger and enter the bore 26 above the seat .28 after the shoulder 34 has seated. This gas,however, could not flow past said seat since the engagement of the shoulder 34 therewith would prevent such occurrence.

The supporting sleeve or nipple I2 is connected at the desired elevation inthe tubing string II and is lowered intothe well casing ID with the tubing. At this time, the valve assembly A is not located within the sleeve i2. After the tubing has been'set within the well casing, a suitable tool (not shown) is engagedwith the fishing neck '23 and the valve assembly is lowered through the well tubing. Of course, at this time there is no gas pressure within the tubing. The valve assembly is lowered through the tubing until the collar 20 and mandrel H at the lower end of said assembly enter the bore I4 of the supporting sleeve l2 and lowering continues until the lower end of the collar is seated on the internal shoulder l3 within said sleeve. The lowering tool (not shown) is then disengaged from the fishing neck 23 and is removed from the tubing, leaving the valve assembly supported within the bore of said tubing.

During the lowering of the valve assembly into its proper position, the valve plunger 30 is in the position shown in Figure 2, being held in such position by the coiled spring 32 which holds the conical head 3| in engagement with the seat 25. The auxiliary lifting fluid, such as gas or air, is then introduced into the upper end of the well tubing II and flows downwardly therethrough. For purposes of this description, it will'be assumed that the lifting medium is gas and said gas is built up to a desired pressure, which pressure is dependent upon the conditions of the particular well.

The gas pressure within the tubing acts against the upper end of the plunger 30 and when such pressure reaches a predetermined point, sufficient to overcome the pressure of the spring 32 and the pressure within the bore of the tubing below the valve assembly, then the plunger is. movedto its lowermost position, with the annular shoulder 34 engaging the seat 28within the lower end of the cylinder (Figure 4) In this position, the bore of the cylinder I5 is closed and the gas in the tubing 1 I above the valve plunger cannot flow downwardly into the tubing below said plunger with As exbly and this pressure is urging. the plunger upwardly. Therefore; it will be seen thatthewell liquid pressure plus the force of the compressed spring is urging the plunger toward a raisedjposition, which movement is resisted by the gas pressure in the tubing acting against theupper end of said plunger.

As the liquid column inthe well casing I and also in the lower portion of the well tubing-ll continues building up .to rise toward anormal standingliquid level, the pressure'within the tubing which is acting against the lower end of the metering pin 33, is'increased. When this pres sure reaches a predetermined point, as determined by the size of the spring 32 and the gas pressure in the upper portion of the tubing, the plunger is moved upwardly against the pressure of the gas, whereby the metering pin 33 is moved upwardly with relation to the reduced portion of the cylinder bore. Such movement of the plunger unseatsthe shoulder 34 andmoves it away from its seat 28, whereby a flow past said seat may occur. At the same time that the upper portion of the pin 33 moves upwardly out of the reduced portion of the bore, the extreme upper ends of the flutes or channels 35 in the plunger move upwardly and out of the reduced portion 2| a of the bore of the upper section l5a of the cylinder. When this occurs, the lifting gas in the tubing l'l above the valve assembly may flow downwardly through the vertical flutes or channels 35 and into the bore 26 of the lower section I 51) of the cylinder. This gas may then how downwardly through the mandrel. and into the tubing below the valve assembly. This admitted gas forces the liquidfromthe lower end of the tubing and upwardly inthe welloasing Ill, said gas following the liquid and escaping upwardly through the well casing. Of course, the charge of admitted gas will naturally lift the fluid through the casing I 0 to the surface.

As soon as upward movement of the, column of liquid in the casing Ill begins, the pressure which has been acting against the underside or lower end of the plunger 30 is reduced. The upper end of the plunger is exposed to the gas pressure which is constant and, therefore, the reduction of the pressure below the plunger causes said plunger to again move downwardly. Such downward movement of the plunger moves the lower reduced end of the metering pin 33 into the reduced portion of the bore 26, and as said pin enters the opening, the cross-sectional flow area of the bore is gradually reduced. This gradual reduction increases the velocity of the gas passing,

around the pin 33 through said bore and, at the same time, a greater cross-sectional pin area is moving into the bore. The increased velocity of the gas flowing through the bore further reduces the pressure below the pin and, also, the pin entering the bore acts with the same effect as a piston within a cylinder, whereby the rate of movement of the plunger is increased as it moves downwardly, The plunger continues its downward movement until the shoulder 34 engages the seat 23. i

The contourv or curvature of the pin is a controlling factor as to the rate or speed of downward movement of the plunger. As shown in the drawings, the curved taper is more or less gradual and therefore as the pin moves into the bore, the reduction of flow area around the pin is relatively gradual and the rate of increase in speed of movement of the plunger is. gradual. If the pin was made with a longer, taper, the reduction of new area and the speed of movement of the pin would be decreased with the result that it would require a longer time for the shoulder 34 to en gage the seat and, thus, more gas would enter the tubing below the valve assembly upon each actuation of the plunger. Similarly, if the contour of the pin were more rounded, the reduction of flow area of the bore would be more abrupt and thereby result in a more rapid downward movement of the plunger. Thus, it will be apparent that by varying the contour of the pin, the time required for the plunger to. complete its downward movement may be controlled, whereby the volume of gas in each charge admitted may be accurately controlled.

As the plunger 30 moves downwardly and the metering pin 33 enters the bore'to reduce the flow area around said pin, the upper ends of the flutes or channels 35 also move downwardly with relation to the reduced portion 2la of the cylinder bore. As has been explained, the upper'endsfof these flutes are gradually reduced and, obviously, as the plunger moves downwardly within the reduced portion-2 la of the cylinderborathe flutes'act to out down the flow area or thesize of the opening through which the gas from above may flow. By controlling or varying the curvature and taper of the upper ends of the flutes, it is possible to accurately meter the flow of gas through the channels in accordance with the movement of the plunger. Thus, it willibe seen that by forming the flutes in the manner shown, it is possible to obtain substantially the same metering action with the flutes, as is obtained by the curved metering pin 33 entering the 'reduced portion of the bore 26. The length of the flutes 35 is such that when the shoulder 34 engages its seat 28 the upper ends of said flutes are within the reduced portion 2la of the cylinder bore and, therefore, the gas from above the plunger is completely shut off and cannot flow through said flutes.

ment, the gas within the bore 26 around the pin 33 can fiow downwardly through the mandrel I1 and this will further lower the pressure below the plunger, whereby the constant gas pressure above the plunger will positively move the shoulder into engagement with its seat. This will assure a-positive and complete shutting off of the gas supply to the liquid column.

After th plunger 30 is seated to close the cylinder bore (Figure 4), the parts remain in this position until the pressure of the well liquidagain builds up to the predetermined point necessary to unseat the plunger upwardly. The size and force of the spring 32 aid in controlling thepressure differential and said spring may be varied to take care of the various well conditions. Obviously, the device operates to admit a charge of gas to raise the well liquid and after the charge is admitted the device positively shuts off the gas until the same is again needed. This makes the valve particularly adapted for use as an intermitter for flowing wells having a relativelylow standing liquid level. I

In the event that the valve plunger should need replacing or in the event that the spring 32 must be changed due to a change in well conditions, it is only necessary to lower a fishing tool .(not shown) and engage the same with the fishing neck 23. The entire valve assembly may then be removed from the well tubing without disturbing said tubing. Removal orinsertion of the device may be on a wire line or cable and may be accomplished in a minimum length of time and with a minimum amount of labor.

The foregoing description of the invention is explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, withinthe scope of the appended claims, without departing from the spirit of the invention.

What we claim and desire to secure by Letters Patent is:

1; A well flowing apparatus including, a well casing having a well liquid inlet, a well tubing extending throughthe well casing and having its lower portion communicating with the bore of the casing, a support connected in the tubing string, a flow valve assembly arranged to be run into and removed from the well tubing and adapted to be removably supported on said sup- POI'hKEIld meansfor introducing a pressure lifting gasintothe upperend of the tubing so that the same flows downwardly therein, the valve assembly including a valve plunger located in theline of flow through the tubing for controlling the admittance of said gas to the liquid in the casing andhaving one end exposed to the gas in the upper end of'the tubing with its opposite end exposed to the pressure of the well liquid in the casing so as to beoperable by a predetermined differential'in such pressures.

2., A well flowingapparatus including a well casing having a well liquid inlet, a well tubing extending through the well casing and having its lower portion communicating with the bore ofthe casing, a support connected in the tubing string, a flow valve assembly arranged to be run into and removed from the well tubing and adapted to be removablysupported on said support, means for introducing a pressure lifting gas: into the upper end of the tubing so that the same flows downwardly therein, the valve assemblyincluding avalveplunger located in the line of flow through, the tubing for controlling the admittance 'of said gas to the: liquid in the casing and having one end exposed to the gas in theupper end of the tubing with its opposite end exposed to the pressure of the well liquid in the casing so as to be operable by a predetermined differentialin such pressures, and means on one extremityof the valve plunger for, metering the Volume of gas flowing past said plunger when the same is in an open position.

BsA well flowing apparatus including, a well casing having a well liquidinlet, a well tubing, extending through the well casing andhavingits lowerportion communicating with the bore of the casing, a support. connected in the tubing string, aflow valve assembly arranged to be run into and removed from: the well tubing and, adapted to beremovably supported, on said support, means for introducing a pressure lifting gas into the upper end of the tubing'so that the same flows downwardly therein, the valve assembly including a valve plunger located in the line of,

flow through the tubing for controllingthe admittance of said gas to the liquid in the casing and: having one and exposed to thegas in the upper end of the tubing with its opposite end exposed to the pressure of the well liquid in the casing, so as to be operable by a predetermined differential in such pressures, means on one extremity ofv the valve plunger for metering the volume of gasflowing past saidplunger when the same is in an open position, and meansformed in the; surface of the plunger for further metering said flow as the plunger is moved toward a closed position.

, 4. A well flowing apparatus including, a well into and. removed from the well tubing and adaptedto be removably supported on said support, and means for introducing a pressure lifting gas into the upper end of the tubing so that the same flows downwardlytherein, the valve assembly including a valve plunger located in the line of flow through the tubing for controlling the admittance of said gas to the liquid in the casing and having one end exposed to the gas in the upper end of the tubing with its opposite end exposed to the pressure of the well liquid in the casing so as tobe operable by a predetermined differential in such pressures, said plunger having a plurality of channels in its surface through which the admitted gas flows, said channels being. constructed to automatically meter the flow as the plunger moves toward a closed position. i

5. As asub-combination in a well flowing apparatus, a: flow device including 'a cylinder having a portion of its bore reduced in diameter, a

flow past the plunger, the extremities of said channels being gradually reduced whereby as said channels move into the bore toward a completely closed position, the flow through said channels is gradually reduced and metered, a tapered metering'element on one end of the plunger, and a valvehead on the opposite end of said plunger, the latter having by-passes therein for permitting a substantially unrestricted flow past the head when the same is in an unseated position.

6. A well flowing device for raising well fluids from a well including, a pair of conduits in said well; said conduits having theirilower ends communicating with each other and one of said conduits having a well liquid inlet whereby the well liquids may rise upwardly therein and may also rise upwardly in the lower portion of the other conduit, a flow valve assembly adapted to be lowered through the bore of the latter conduit and removably supported therein, said assembly including a'valve element and seat for closing the bore of the conduit within which the assembly is supported, said valve element being located in the line; of flow through theaconduit whereby opposite ends thereof are exposed to the pressures on opposite sides of the assembly, and means for introducing a lifting fluid into the conduit above the valve assembly, whereby the lifting fluid to the well having an internal tapered seating surface, a flow valve assembly adapted to be lowered through the tubing and removably supported on said seating surface, the assembly including a tubular housing having a valve seat therein, a spring pressed valve member for controlling fiow through said housingto control flow through the tubing, said valve member being located in the line of flow through the conduit in which the assembly is mounted, whereby opposite ends of said member are exposed to the pressures on opposite sides of said assembly, and means for introducing a lifting fluid into the tubing above the assembly, whereby the pressure of said lifting fluid holds the assembly on the seat and also acts against one side of the member tourge the same toward a closed position.

8. A well flowing device including, a well liquid l flow line, a well tubing having its lower end communicating with the flow line, an elongate supporting nippleconnected in the well tubing and having "an internal tapered seating surface, a flow valve assembly adapted to be lowered through the tubing and removably supported on said seating'su'rface, theassembly including a tubular housing having a valve seat therein, a spring pressed valve member for controlling flow through said housing'to control flow'through the tubing, said valve member being located in the line of flow through the conduit in which the assembly is mounted, whereby opposite ends of saidmember are exposed to the pressures on opposite sides of said assembly, means for introducing'a' lifting fluid into the tubing above the assembly, whereby the pressure of said lifting fluid holds the assembly on the seat and also acts against one side of the member to urge the same toward a closed position, and pressure seal packing means interposed between the assembly and the bore of the nipple and acted upon by the lifting fluid pressure jtopack off around said assembly.

9. A well blowing device including, a well liquid flow line, a well tubing having its lower end communicating with the flow line, an elongate supporting nipple connected in the Well tubing and having an internal tapered seating surface, a flow valve assembly adapted to be lowered through the tubing and removably supported onsaid seating surface, the assembly including a tubular housing having a valve seat therein, a springpressed valve member for controlling fiow through said housing to control flow through the tubing, said valve member being located in the line of flow through the conduit in which the assembly is mounted, whereby opposite ends of said member are exposed to the pressures on opposite sides of said assembly, and means for introducing a lifting fluid into the tubing above the assembly, whereby the pressure of said lifting fluid holds the assembly on the seat and also acts against one side of the member to urge the same toward a closed position, the valve member having a plurality of vertical channels in its external surface, said channels being reduced toward their ends to meter the flow of fluid passing the member when the same is in an open position. i

10. The combination with a flow conduit having its lower end communicating with a well liquid flow line, of a flow valve assembly including a housing adapted to be lowered through the conduit and removably seated therein, said housing having a bore communicating with the operable by the differential in such 2,268,041, p'ortingnipple connected. in the well tubing and bore of the conduit, a movable valve element located in the line of flow through'the conduit for closing the bore of the housing and having its lower end exposed to the pressure in the liquid flow line and its upper end exposed to pressure in th conduit thereabove, and means for introducing a pressure lifting into the upper end of the conduit, whereby the valve element is actuated by the pressure differential thereacross to admit the lifting fluid to the flow line, the lifting fluid pressure also acting downwardly on the assembly to hold the same in its seated within the conduit.

11. The combination with a flow conduit having its lower end communicating with a well liquid flow line, of a flow valve assembly including a housing adapted to be lowered through the conduit and removably seated therein, said housing having a bore communicating with the bore 'of the conduit, a movable valve element located in the line of flow through the conduit for closing the bore of the housing and having its lower end exposed to the pressure in the liquid flow line and its upper end exposed to pressure in the con- 1 duit thereabove, means for introducing a pressure lifting into the upper end of the conduit, whereby the valve element is actuated by the pressure differential thereacross to admit the lifting fluid to the flow line, the lifting fluid pressure also acting downwardly on the assembly to hold the same in its seated position within the conduit, the valve element havinga longitudinal channel in its external surface which channel is gradually reduced in area toward the extremity of the ele ment to meter the flow of fluid past the element when the same is in an open position.

' 12. A well flowing device including, a well tubing, a flow line communicating with the lower end of thetubing, a support connected in said tubing and having an internal seat, a flow valve assembly adapted to be run into the well through the bore of the tubing and arranged to engage the seat so as to be removably supported in the tubing bore, the assembly having a flow passage which communicates with the tubing bore, means having opposite ends exposed to the pressures on opposite sides of the passage within the passage operable by the pressure differentialthereacross for controlling the flow therethrough, and means for introducing a lifting gas into the upper end of the tubing, whereby the flow of said gas downwardly through the tubing and into the flow line is controlled by the valve assembly.

13. A well flowing device including, a well tubing, .a flow line, communicating with the lower end of thetubing, a support connected in said tubing and having an internal seat, a flow valve assemblyadapted to be run through the bore of the tubing and arranged to engage said seat so as tobe supported thereby, means for sealing ofi the: space between the assembly and tubing bore when the former is in position therein, means within the assembly having opposite sides exposed to the tubing and flow line pressures and pressures for controlling the flow through the assembly, and means for introducing a lifting gas into the upper end of the tubing, whereby the flow of said gas downwardly through the tubing and to the flow line is controlled by the valve assembly.

position string above the point of communication between the tubing and easing, a flow valve assembly arranged to be run into and removed from the well tubing and adapted to be removably supported on said support, said assembly including a valve seat and valve member adapted to engage the seat to close the flow through the assembly and through the tubing, said valve member having one end exposed to the pressure in the tubing above the assembly with its other end exposed to the pressure in the tubing below the assembly, whereby the valve member is actuated by the differential in such pressures, and means for introducing a lifting gas into the upper end of the tubing, whereby the valve means controls the admittance of said gas to the lower portion of the tubing and then to the well liquid in the casing.

15. A well flowing apparatus including, a well casing having a well liquid inlet, a well tubing extending through the well casing and having its lower portion communicating with the bore of the casing, a support connected in the tubing string, a flow valve assembly arranged to be run into and removed from the well tubing and adapted to be removably supported on saidsupport, said assembly including a valve element located in the line of flow through the tubing for closing the bore of the tubing, said element having one side exposed to thepressure of the tubing above the assembly and its other side exposed to the pressure in the casing, whereby it is actuated by the differential in such pressures, means for introducing a lifting gas into the upper end of the tubing, whereby the valve means controls the admittance of said gas to the lower portion of the tubing and to the well liquid in the casing, and pressure seal packing means exposed to the gas pressure in the tubing above the valve assembly for packing off between said assembly and said support.

ROY A. LAMB. WILLIAM H. WARING. 

